Who studies tectonic plates and the planet's crust?

edit: this is supposed to be geography

All living things share certain characteristics. which of the following characteristics is not shared by all living things?

This territory was the site of numerous spanish missions but was severely depopulated in the 17th century by infectious disease and warfare with other indian tribes

Which of the following  bestillustrates a negative reinforcer?               a.  copland gives up candy to stave off chronic acid indigestion.    b.  nancy learns that she prefers chocolate over vanilla.    c.  carmine changes his major to english lit after failing a math exam.    d.  on a hot day, lindberg always drinks lemonade.